Application of nonlinear methods in tracking failure test of epoxy/SiO2 nanocomposite

This paper investigates the effect of nano-scale SiO₂ on the tracking failure properties of nanocomposites. Test samples were made by dispersing nano-scale SiO₂ powder in epoxy with the weight ratios of 0, 1, 3, 5, 7, 9 wt%. AC voltage was applied on a pair of needle-plate electrodes at the surface with the insulation distance of 10 mm. The time to tracking failure and discharge current were recorded. In order to distinguish the change of the tracking resistance from the confusing discharge current, a recurrence plot (RP) analysis of discharge current has been used. The patterns of the tracking failure were analyzed with fractal dimension (FD) method to quantify the carbonization degree. The results reveal that 3 wt% of nano-scale SiO₂ filler greatly increase the resistance to tracking failure of epoxy/SiO₂ nanocomposite.